The political world has lost a legendary member.

Sen. Dianne Feinstein, who became the longest-serving woman in the U.S. senate with over three decades in office, passed away on Sept. 28. She was 90.

According to a Sept. 29 statement from her office, Feinstein died at her home in Washington, D.C. "Her passing is a great loss for so many," the message—posted to X, formerly known as Twitter—read, "from those who loved and cared for her to the people of California that she dedicated her life to serving."

Feinstein, who was first elected to the coveted position in 1992, was also the oldest senator in U.S. history. The San Francisco native, who faced health struggles over the years, shared her plans to retire from congress back in February. 

"I am announcing today I will not run for reelection in 2024," she said in a statement at the time, "but intend to accomplish as much for California as I can through the end of next year when my term ends."

Following her announcement, President Joe Biden praised Feinstein's work over the years, calling her a "passionate defender of civil liberties and a strong voice for national security policies that keep us safe while honoring our values."

"I've served with more U.S. Senators than just about anyone," Biden noted. "I can honestly say that Dianne Feinstein is one of the very best. I look forward to continuing to work with her as she serves out her term."

After her death was announced on Sept. 29, many of Feinstein's supporters, as well as fellow politicians and stars, paid tribute to her online. 

"The senior senator of my home state of California, Dianne Feinstein, has passed away at age 90," actor George Takei wrote on X, formerly known as Twitter. "She was a trailblazer and a leading advocate for an assault weapons ban. May she rest in peace, and may her memory be a blessing."

NBC News was first to report Feinstein's passing.

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